The present invention relates to a method, and a device for performing it, for making parts of a graphics display such as for example specific characters or lines which are being displayed thereon stand out distinctly from other parts of the display, typically from the main part of the display. The present invention is particularly effective for utilization with a monochromatic graphic display device, but is also applicable to a multi color graphic display device such as a color CRT monitor.
This making parts of the display more prominent is required in the current computer graphic display art, for example when displaying statistical data and design plans for machinery or buildings. For example, such a process and device are used in the processes of graphic design of automobiles, ships, industrial machines, industrial plants, printed circuit boards, integrated circuits, LSI circuits, and buildings. In these graphic display processes, various data including drawings are displayed on a graphic display device such as a CRT, according to data and commands from an input device or data and commands from a computer system.
Conventionally two methods have been practiced to make a certain or specific portion of a graphics display on such a monochromatic display device distinct from the other portions of the display. One is the method of causing the specific portion to flash, and the other is the method of making it distinct by causing it to have a different light emitting intensity, i.e. to be brighter or darker than the rest of the graphics display.
However, according to the above described conventional methods, when the flashing or the particular light emitting intensity of the specific portion is desired to be changed, (for instance when the light emitting intensity or brightness of the specific portion is desired to be reduced gradually), the light emitting intensity or the flashing condition is changed by a computer, which has to issue instructions each time that this has to be done. The computer is required to execute a program in order to determine these instructions, repeatedly, and the processing time of this program is quite considerable, so that most of the time of the computer is taken up by this display alteration task. The main task of the computer is subordinate to the task of display alteration, being put onto standby while the display is altered, and the execution time for this main task is accordingly prolonged.
Now, it is known in the art to alter the light emitting intensity of the entire screen of the graphic display device simultaneously in the same way with hardware, and in this case the same light intensity alteration computation is carried out for each of the pixels on the screen; but it has not been previously known or contemplated for the light emitting intensity of individual pixels on the screen or for the light emitting intensity of certain parts of the screen to be altered in a different manner from others by hardware.